Astronomy Visualization Metadata (AVM) Standard - Version 1.1 DRAFT International Virtual Observatory Alliance Astronomy Visualization Metadata (AVM) Standard for the Virtual Astronomy Multimedia Project (VAMP) and other Virtual Observatories. Version 1.10 - DRAFT IVOA DRAFT Note 2008 Jan 5 Working Group: not applicable Authors: Robert Hurt, Lars Lindberg Christensen, Adrienne Gauthier with input from the IAU Virtual Astronomy Multimedia Project (VAMP) Working Group under IAU Commission 55 Communicating Astronomy with the Public Editors: Lars Lindberg Christensen, Robert Hurt, Adrienne Gauthier Abstract This document describes a standard for Astronomy Visualization Metadata (AVM) that can span both “photographic” images produced from science data and “artwork” illustrations. This standard will allow individual image files to be catalogued and offered through searchable databases and is the keystone to the VAMP project. The standard includes both the metadata schema for describing outreach images and the method by which the metadata may be embedded within the image file. Embedded metadata are commonly in use in digital photography and the publication industry, and the standard described here easily integrates into those workflows. For data-derived images, full World Coordinate System (WCS) tags can be used to describe fully the position, orientation, and scale of the image while allowing for a variety of applications requiring the full coordinate context. 2006-06-30, current edit 2007-11-5 DRAFT Page 1 of 66 Astronomy Visualization Metadata (AVM) Standard - Version 1.1 DRAFT Status of this document This is an IVOA Proposed Recommendation made available for public review. It is appropriate to reference this document only as a recommended standard that is under review and which may be changed before it is accepted as a full recommendation. Nov 5 2007: Currently under edit/revision by AJ Gauthier/R Hurt/ LL Christensen Jan 5 2008: Final revision prior to AAS feedback session Acknowledgements This document is a product of discussions started in IAU Commission 55 Communicating Astronomy with the Public and the subsequent Virtual Repository Working Group, now named Virtual Astronomy Multimedia Project (VAMP). The editors gratefully acknowledge the many significant comments, discussions, and contributions from the many participants in this group. Revision History AVM Version 1.0: September 2006 AVM Version 1.1: DRAFT October 2007 – January 2008 Modifications from v1.0 to v1.1: • Editor’s Notes added for more effective community feedback discussions • More detailed information added for each tag definition • Redesigned informational tables to show proper example metadata, tags, IPTC, and UCD1+ equivalencies/translations • Full example XMP file added into Appendix • Reformat of Section 4: Metadata Definitions • Various text/wording modifications and new sections of text were added. • Added more footnotes to software packages, existing standards, and organizations • Reference to AVM Users Guide for Dummies added in 1.5 Implementation • Addition of new Appendice, C: WCS Representation in the AVM. Consequently, Appendix C from Version 1.0 is now Appendix D and Appendix D from Version 1.0 is now Appendix E. Modifications to Existing Tags: • ‘Coverage’ removed from ‘Spatial.’ tags as it was deemed unnecessary • ResourceID now reflects a content provider’s naming schema for their image files. Used now in conjunction with the new tag ResourceURL. 2006-06-30, current edit 2007-11-5 DRAFT Page 2 of 66 Astronomy Visualization Metadata (AVM) Standard - Version 1.1 DRAFT • Section 2.2 Recommended Levels of Tagging replaces “Levels of Requirement” to better describe why certain metadata fields are necessary and the effects if tags are left out of a submission. • A new Type of image was added: Collage • CreatorURL now references the IPTC tag Iptc4xmpCore:CiUrlWork. • The definition of Headline now follows the IPTC standard of a “short description” rather than a “title” for the image as in Version 1.0. • MetadataVersion now resides in the Publisher tagset. New Tags: • The Title tag now holds the data formerly in Headline as Headline was redefined. • MetadataDate under Publisher tagset • ResourceURL under Publisher tagset • RelatedResources under Publisher tagset Retired Tags: CDMatrix 2006-06-30, current edit 2007-11-5 DRAFT Page 3 of 66 Astronomy Visualization Metadata (AVM) Standard - Version 1.1 DRAFT ABSTRACT .................................................................................................................................................. 1 STATUS OF THIS DOCUMENT............................................................................................................... 2 ACKNOWLEDGEMENTS ......................................................................................................................... 2 REVISION HISTORY................................................................................................................................. 2 1 OVERVIEW........................................................................................................................................ 7 1.1 INTENDED SCOPE OF AVM METADATA SCHEMA......................................................................... 7 1.2 METADATA PORTABILITY: XMP.................................................................................................. 7 1.3 REFERENCED STANDARDS ........................................................................................................... 8 1.4 WORLD COORDINATE SYSTEM NOTES ......................................................................................... 9 1.5 IMPLEMENTATION ........................................................................................................................ 9 2 AVM METADATA TAG DESCRIPTIONS .................................................................................. 10 2.1 TAG FORMATS............................................................................................................................ 10 2.2 RECOMMENDED LEVELS OF TAGGING........................................................................................ 11 AVM SCHEMA SUMMARY TABLES ................................................................................................... 13 2.3 AVM EXAMPLE TAGS AND METADATA..................................................................................... 13 2.4 AVM TECHNICAL TABLE........................................................................................................... 15 3 METADATA DEFINITIONS.......................................................................................................... 18 3.1 CREATOR METADATA ................................................................................................................ 18 Creator................................................................................................................................................ 18 CreatorURL ........................................................................................................................................ 19 Contact.Name ..................................................................................................................................... 19 Contact.Email ..................................................................................................................................... 19 Contact.Telephone .............................................................................................................................. 20 Contact.Address.................................................................................................................................. 20 Contact.City ........................................................................................................................................ 20 Contact.StateProvince ........................................................................................................................ 21 Contact.PostalCode ............................................................................................................................ 21 Contact.Country.................................................................................................................................. 21 Rights .................................................................................................................................................. 22 3.2 CONTENT METADATA ................................................................................................................ 22 Headline.............................................................................................................................................. 22 Title..................................................................................................................................................... 23 Subject.Category................................................................................................................................. 23 Subject.Name ...................................................................................................................................... 23 Description.......................................................................................................................................... 24 ReferenceURL..................................................................................................................................... 24 Credit